The Food and Drug Administration said on Tuesday it has stopped all pediatric clinical trials of Amgen Inc's Sensipar after the death of a 14-year-old patient taking part in a study of the drug. Sensipar, which is approved for adults, is used to lower dangerously high calcium levels in the blood. The agency said it was collecting information on the circumstances of the teenager's death. It said it does not know if the Amgen drug had any role in the death. "This communication is intended to inform health care professionals that we are evaluating the information and will communicate our final conclusions and recommendations when our review is complete," the FDA said in a statement posted on its website. Amgen, the world's largest biotechnology company, said it had sent a letter last week to healthcare providers alerting them to the trials' halt and the patient death. "Amgen is working as rapidly as possible to understand the circumstances of what happened. This analysis is ongoing and will be concluded as quickly as possible," the company said in a statement.